Watches equipped with a magnifier at the level of their glass in order to magnify the display of the day of the month have been known for a long time. According to a first variant, the magnifier is machined into the watch glass. In another variant, a magnifying lens is glued under the interior face of the glass.
Such a magnifier is valued by users because the size of the window and the imprint of the day of the month are often of very small dimensions, in particular when the days of the month are imprinted on a single ring or disc. However, some consumers consider that a magnifier impairs the beauty of the watch and therefore poses an aesthetic problem. In fact, a magnifier often gives the watch a retro look. Moreover, it causes optical deformation of the dial when viewed from a distance or obliquely.
In order to remedy this problem, watchmakers have proposed watches with a “large date”, also termed watches with a “large window”, with reference to the window provided in the dial in order to display the day of the month. Such a solution makes the watch movement more complex and therefore increases the production costs thereof. Furthermore, a large window occupies more space on the dial and the associated mechanism is often relatively cumbersome at the level of the bottom plate of the watch movement so that this solution limits the possibilities for arranging other information. Finally, some embodiments place the tens and the units of the day of the month on different levels, which is generally visible.